Abstract #T354

# T354
Growth performance of yellow cattle in southern China weaned at different ages.
C. Wang*1, Y. F. Xia1, H. L. Mao1, Y. Tu2, C. G. Jiang2, H. F. Wang1, Q. Y. Diao2, D. X. Ren3, 1College of Animal Science and Technology, Zhejiang A & F University, Hangzhou-Lin’an, Zhejiang Province, China, 2Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China, 3Institute of Dairy Science, Zhejiang University, Hangzhou, Zhejiang Province, China.

This study was conducted to examine the effects of weaning ages on performance of a small-type yellow cattle in southern China. Thirty female calves were selected according to birth weight, and stratified into 10 blocks of 3 and allocated within block to 3 treatments that the calf was considered weaned when it consumed 1000 (W1000), 750 (W750), or 500 (W500) g of starter for 2 consecutive days. All calves had colostrum within 4 h after born, and then were fed milk up to 3 L/d until d 7. Liquid feed composed of half whole milk and half milk replacer (MR, 93.2% DM, 23.9% CP, and 13.1% EE) were fed to calves at 3L/d until d 13 and 3 L/d MR for the remainder of the study. Starter (17.9% CP, 10.9 MJ/kg ME) was fed ad libitum from d 10, and grass hay and water were available ad libitum. Milk, MR, starter, and hay intakes were recorded daily. All Claves were weighted and body height, body length, circumference of cannon bone were measured after birth and every 30 d until d 150. Data except for weaning age and BW change were analyzed using the Proc MIXED of SAS while weaning age and BW change were analyzed using the Proc GLM of SAS. The results showed that average weaning age was 49 ± 4.8, 58 ± 4.4, and 63 ± 4.6 for W500, W750, and W1000, respectively. Calves in W500 and W750 had higher starter intake than that of W1000 (P < 0.05). The body measurements were not significant different between groups (P > 0.05), however, calves in W1000 tend to have a low body height and body length (0.05 < P < 0.15). There was no significant difference in BW and ADG on d 30 when any of the calves was weaned (P > 0.05). On d 60, BW of calves in W1000 was higher than that of W500 (P < 0.05) and tend to be higher than that of W750 (P = 0.10). However, calves in W1000 lost their BW advantage on d 90. Calves in W750 and W500 had higher ADG from 1 to 150 d compared with that of W1000. It is concluded that starter-dependent weaning can help to enhance the adaptation to the solid feed with advantages on weight gain and feed intake.

Key Words: weaning, yellow cattle, growth performance